What is Setlocal in batch file?

setlocal localizes changes that are made to variables (in the documentation referred to as environment). The changes are reverted back with endlocal . setlocal is affected by whether command extensions are enabled or disabled. setlocal has no effect when not used in a batch file.

What does Setlocal EnableDelayedExpansion do?

Delayed Expansion will cause variables within a batch file to be expanded at execution time rather than at parse time, this option is turned on with the SETLOCAL EnableDelayedExpansion command. By default expansion will happen just once, before each line is executed.

What are command extensions?

Command Extensions. Command extensions enable extra features in NT shells. By default command extensions are enabled. However, to be absolutely sure that they are, either use SETLOCAL ENABLEEXTENSIONS within your NT shell scripts (batch files) or execute those scripts using CMD /X .

What is Endlocal?

The endlocal command is used to stop the localization of the environment changes enabled by the setlocal command.

What does EnableExtensions do?

EnableExtensions Attempt to enable Command extensions. DisableExtensions Attempt to disable Command extensions. SETLOCAL on it’s own, usually at the start of a batch file, will begin localisation of Environment Variables.

What does a cmd do?

It can be used to execute entered commands and perform advanced administrative functions. It can also be used to troubleshoot and solve certain kinds of Windows issues.

Do I need setlocal enableextensions to enable command extensions?

So theoretically, you do not need to enable it using setlocal ENABLEEXTENSIONS. Most bat scripts do use “setlocal ENABLEEXTENSIONS” to enable command extensions explicitly to make it clear and absolute.

What is setlocal used for?

The most frequent use of SETLOCALis to turn on command extensions and allow delayed expansion of variables: SETLOCAL ENABLEEXTENSIONS ENABLEDELAYEDEXPANSION For more info on SETLOCALsee the Command Line Referenceat Microsoft TechNet.

What are the changes to setlocal?

If Command Extensions are enabled SETLOCAL changes as follows: SETLOCAL batch command now accepts optional arguments: Enable or disable command processor extensions. See CMD for details. Enable or disable delayed environment variable expansion. See SET /? for details.

Why does setlocal always set an errorlevel?

When run from a batch file, SETLOCAL will always set an ERRORLEVEL. Command Extensions are enabled by default, there is rarely any need to disable them. If Command Extensions are permanently disabled or if a script is running under the Windows 95 command processor command.com then SETLOCAL ENABLEEXTENSIONS will not be able to restore them.

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